Holding apparatus for the end of a sheet coil

ABSTRACT

The holding device according to the invention for the sheet end  12  of a material web wound up to form a coil  1 , which material web is received on a carrying shaft  44 , comprises a clamping bar  34  on which several clamping pieces  35  are arranged so as to be displaceable and fixable along the longitudinal axis of the clamping bar  34 , which is supported on the ends of the carrying shaft  44  by clamping and guiding units  36  via bearing pieces  45  and exerts a contact pressure between the bottom side of the sheet end  12  and the penultimate layer of the coil  1  and between the top side of the sheet end  12  and the clamping pieces  35 , which contact pressure, together with the frictional forces resulting therefrom, secures the sheet end  12.    
     For the purpose of mounting and dismantling the clamping bar  34 , the compression springs  39  provided in the clamping and fixing units  36  are prestressed by hand-operated eccentric levers  47  engaging the pins  41  and  42  in such a way that said clamping bar can be placed onto the guide rods  43  without force and, respectively, can be removed therefrom, provided that the spring-loaded flaps  40  are manually prevented from locking into place on the toothing systems of the guide rods  43.    
     With a decreasing unwinding radius, the spring-loaded flaps  40  will lock into place on the toothing systems of the guide rods  43  according to said decrease. 
     The clamping pieces  35  arranged on the clamping bar  34  in a displaceable and fixable manner produce the required clearances for strappings  20  of the coil  1 , which are present during the assembly and, respectively, are necessary before removal.

The invention relates to a holding device for a sheet end of a materialweb wound up to form a coil, which material web is received on acarrying shaft.

Sheet metal working plants are already known in which any number ofsheet coils (also of different kinds) are supplied from a storage areato a feed device of such plants using transport carts.

The sheet coils are usually received on clamping mandrels which have acarrying shaft in the middle and in which several clamping arms arearranged toward the inner surface of the coil. The coil is therebyfastened to the carrying shaft in a central and correct position.

It is now the object of the invention to provide a holding device of theinitially described kind which meets the following requirements:

-   -   holding the end of the material web, in particular sheet web,        wound up to form a coil safely and in a correct position,    -   mounting the holding device onto coils of any as-delivered        condition (mainly onto coils which are fixed during transport        and storage by strappings with sheet metal bands—frequently        arranged along the periphery thereof) without using specific        auxiliary means,    -   enabling a space-saving design of the storage areas for the        coils,    -   unwinding the coils with both the outside and the inside facing        upwards,    -   easy opening of the holding device in the feed device of the        material web processing plant.

According to the invention, said object is achieved in that a clampingbar arranged parallel to the carrying shaft and extending across thewidth of the material web is clampable on the end side against thematerial web with a clamping device in each case, which always rests onthe carrying shaft also on the end side.

Advantageous advanced embodiments of the invention are characterized inthe dependent claims.

The holding device according to the invention comprises two componentparts (arms) each provided at the projecting ends of the carrying shaft,which pull or push a clamping bar connecting those two component partsagainst the centre of the coil axis in order to thereby fasten the endof the wound-up material web to the coil itself.

If a sufficiently large tensile force/compressive force is now providedbetween the clamping bar and the coil axis, the end of the material webis held safely because of the contact pressure prevailing between thebottom side thereof and the penultimate layer of the coil and because ofthe same contact pressure prevailing between the top side thereof andthe clamping bars and because of the frictional forces resultingtherefrom, even if the above-mentioned component parts provided on bothsides are mounted to the carrying shaft in principle in a loose (e.g.,rotatable) manner.

The displaceable clamping pieces arranged on the clamping bar producethe required clearance for the strappings which generally are providedon the delivered coils. The holding device can be mounted to the coilwithout any problems despite those strappings—the sheet end can be fixedwithout any difficulties—and the strapping can then be removed safely.

The holding device is designed and mounted such that, if several coilswith a longitudinal axis oriented in parallel are stored in a line inthe storage area, no additional storage space is taken up by them.

The holding device allows the sheet web to be pulled off and also to bewound up, respectively, in a tangential manner by any kind of draw-indevice of, e.g., sheet metal working machines.

Below, the invention is illustrated in further detail based on exemplaryembodiments, with reference to the drawings.

FIG. 1 schematically shows a processing device for sheet coils.

FIG. 2 a shows a side view of a sheet coil provided with a holdingdevice, the holding device being designed with arms that are hooked in.

FIG. 2 b shows a respective front view.

FIG. 3 a shows a side view of a sheet coil provided with a holdingdevice, the holding device being designed with arms mounted onto thecarrying shaft.

FIG. 3 b shows a respective front view.

FIG. 4 a shows a side view of a sheet coil provided with a holdingdevice, the holding device being designed with arms mounted onto thecarrying shaft and the clamping force showing only small variationsdespite large differences in diameter.

FIG. 4 b shows a respective front view.

FIG. 1 shows the storage area (stockpiling) of a sheet metal workingplant with a random number of coils 1 which are set down on pillowblocks 2. Using a transport cart, which is not illustrated here, therespective coil 1 required by the plant is lifted from the pillow block2 and placed into the feed device 3. Said device generally has a drivewhich supports the pulling-off of the sheet from the coil 1 and,respectively, accomplishes the winding of sheet which has not beenprocessed by the plant. The holding device 4 according to the inventionsecures the end of the sheet web of the coil 1.

If the sheet metal working plant requires that, during processing of thesheet web, the outside of the coil 1 must lie on top, the coil 1 isdeposited in the storage area according to depot variant A. If the sheetmetal working plant requires that, during processing of the sheet web,the inside of the coil 1 must lie on top, the coil 1 is deposited in thestorage area according to depot variant B.

FIG. 2 a shows a side view of a sheet coil 1 provided with a holdingdevice, the holding device being designed with arms that are hooked in.FIG. 2 b shows the respective front view.

The holding device comprises a clamping bar 5 on which several clampingpieces 6 are arranged so as to be displaceable and fixable along thelongitudinal axis of the clamping bar 5. The clamping bar 5 is securelyconnected on either end to one connecting rod 7 each. Those connectingrods 7 are received in longitudinal guides 8 in the hinge parts 10. Thecompression springs 9 located therebetween push the connecting rods 7along with the clamping bar 5 with its clamping pieces 6 toward thecentre of the carrying shaft 11, on which the coil 1 is stretched.

In the position which is shown (clamping position), a contact pressureprevails between the bottom side of the sheet end 12 and the penultimatelayer of the coil 1—just like between the top side of the sheet end 12and the clamping pieces 6. Said contact pressure and the frictionalforces resulting therefrom secure the sheet end 12 against being unwoundas well as against being extracted.

In the feed device 3, the two hinge parts 10 are pressed againstexisting stops 16 on lugs 14 provided therefor by means of appropriateactuators 15 in such a way that the carrying shaft 11 is able to runcompletely freely. The clamping bar 5 is likewise pressed againstexisting stops 19 on lugs 17 provided therefor by means of appropriateactuators 18 in such a way that the sheet web is able to run offcompletely freely. By means of the clamping elements 13 arranged on thetwo hinge parts 10, the compression springs 9 can be prestressed for thepurpose of mounting (assembly operation) and dismantling (removaloperation) in such a way that the holding device can, as a whole, beplaced onto and removed from, respectively, the coil 1 with the carryingshaft 11. The clamping of the sheet end 12 is effected by loosening theclamping elements 13 during the assembly operation. The detachment ofthe sheet end 12 is effected by tightening the clamping elements 13during the withdrawal operation.

The displaceable clamping pieces 6 on the clamping bar 5 enable therequired clearances for strappings 20 of the coil 1, which generally arepresent during the assembly. They also enable the remainder of the coilto be strapped in a desired removal operation of the holding device.

FIG. 3 a shows a side view of a sheet coil 1 provided with a holdingdevice, the holding device being designed with arms mounted onto thecarrying shaft. FIG. 3 b shows the respective front view.

The holding device comprises a clamping bar 21 on which several clampingpieces 22 are arranged so as to be displaceable and fixable along thelongitudinal axis of the clamping bar 21. The clamping bar 21 isconnected on either end to one connecting rod 24 each by means ofplug-and-socket connections 23. The connecting rods 24 are received inlongitudinal guides 25 in the bearing pieces 27. The compression springs26 located therebetween push the connecting rods 24 along with theclamping bar 21 with its clamping pieces 22 toward the centre of thecarrying shaft 28, on which the coil 1 is stretched.

In the position which is shown (clamping position), a contact pressurenow prevails between the bottom side of the sheet end 12 and thepenultimate layer of the coil 1—just like between the top side of thesheet end 12 and the clamping pieces 22. Said contact pressure and thefrictional forces resulting therefrom secure the sheet end 12 againstbeing unwound as well as against being extracted.

In the feed device 3, the clamping bar 21 is pressed against existingstops 31 on lugs 29 provided therefor by means of appropriate actuators30 in such a way that the sheet web is able to run off completelyfreely. Since the bearing pieces 27 are rotatably mounted onto thecarrying shaft 28, they do not have to be disengaged separately.

By means of the clamping elements 32 arranged on the two bearing pieces27, the compression springs 26 can be prestressed for the purpose ofmounting (assembly operation) and dismantling (removal operation) insuch a way that the clamping bar 21 can be inserted and removed,respectively, without force. Since the bearing pieces 27 are rotatablymounted onto the carrying shaft 28, they must be kept in the desiredperipheral position during the assembly using fixing devices 33. Theclamping of the sheet end 12 is effected by loosening the clampingelements 32 during the assembly operation. The detachment of the sheetend 12 is effected by tightening the clamping elements 32 during thewithdrawal operation.

The displaceable clamping pieces 22 on the clamping bar 21 enable therequired clearances for strappings 20 of the coil 1, which generally arepresent during the assembly. They also enable the remainder of the coilto be strapped in a desired removal operation of the holding device.

FIG. 4 a shows a side view of a sheet coil 1 provided with a holdingdevice, the holding device being designed with arms mounted onto thecarrying shaft and the clamping force showing only small variationsdespite large differences in diameter. FIG. 4 b shows the respectivefront view.

The holding device comprises a clamping bar 34 on which several clampingpieces 35 are arranged so as to be displaceable and fixable along thelongitudinal axis of the clamping bar 34. The two ends of said clampingbar 34 are formed by clamping and guiding units 36. External guide tubes38 are securely connected to the clamping bar 34. Internal guide tubes37 rest on the guide rods 43, namely with a positive fit on toothingsystems of the guide rods 43, via spring-loaded latches 40. In theposition which is shown (clamping position), compression springs 39located therebetween push the external guide tubes 38 along with theclamping bar 34 and the clamping pieces 35 toward the centre of thecarrying shaft 44, on which the coil 1 is stretched.

In the position which is shown (clamping position), a contact pressurenow prevails between the bottom side of the sheet end 12 and thepenultimate layer of the coil 1—just like between the top side of thesheet end 12 and the clamping pieces 35. Said contact pressure and thefrictional forces resulting therefrom secure the sheet end 12 againstbeing unwound as well as against being extracted.

The guide rods 43 are received in the bearing pieces 45.

In the feed device 3, the clamping and guiding units 36 are pushed aparton lugs (pins) 41 and 42 provided therefor by means of appropriateactuators 46 (spreaders). The result is that the clamping bar 34 islifted from the clamped sheet end 12 in such a way that the sheet web isable to run off completely freely. Since the bearing pieces 45 arerotatably mounted onto the carrying shaft 44, they do not have to bedisengaged separately. If the final positions of the pins 41 and 42 endup lying symmetrically to the sheet plane of the sheet end 12 with theactuator 46 being spread apart, this kind of opening the holding deviceis applicable for both unwinding variants.

Since, during the unwinding operation, the feed device 3 fulfills thefunction of keeping the level of the sheet that has been pulled offtangentially constant also with a decreasing outside diameter of thecoil, said device must continuously lift and lower, respectively, thecentre of the sheet coil. During said operation, the guide rods 43 nowslide permanently in the inner guide tubes 37, which are supported onthe pins 42 by the spread-apart actuators 46. With a correspondingdecrease in the outside diameter of the coil, the spring-loaded flaps 40will lock into place on the guide rods 43 accordingly.

After loosening the spread of the actuators 46, the clamping rod 34along with its clamping pieces 35 is pushed back toward the centre ofthe coil axis by the compression springs 39 along the guide rods 43 dueto the support of the inner guide tubes 37 by the spring-loaded flaps40, and the sheet end 12 is fastened to the coil 1.

Using an appropriate hand-operated eccentric lever 47, the compressionsprings 39 of the clamping and fixing units 36 can be prestressed viatheir pins 41 and 42 for the purpose of mounting (assembly operation)and dismantling (removal operation) in such a way that the clamping bar34 can be inserted and removed, respectively, without force, providedthat the spring-loaded flaps 40 are manually prevented from locking intoplace when the clamping bar 34 is being removed. Since the bearingpieces 45 are rotatably mounted onto the carrying shaft 44, they must bekept in the desired peripheral position during the assembly usingfixation means 48.

The displaceable clamping pieces 35 on the clamping bar 34 enable therequired clearances for strappings 20 of the coil 1, which generally arepresent during the assembly. They also enable the remainder of the coilto be strapped in a desired removal operation of the holding device.

1. A holding device for a sheet end (12) of a material web wound up tofaun a coil (1), which material web is received on a carrying shaft(44), characterized in that a clamping bar (34) arranged parallel to thecarrying shaft (44) and extending across the width of the material webis clampable on the end side against the material web with a clampingdevice (36) in each case, which always rests on the carrying shaft (44)also on the end side.
 2. A holding device according to claim 1,characterized in that, on the clamping bar (34), two or several clampingpieces (35) are arranged so as to be displaceable along the longitudinalaxis of the clamping bar (34) and optionally so as to be fixable on theclamping bar (34).
 3. A holding device according to claim 1,characterized in that the clamping device (36) is supported on the endregions of the carrying shaft (44) via bearing pieces (45).
 4. A holdingdevice according to claim 1, characterized in that the clamping device(36) is also designed as a guiding device for the clamping bar (34)toward the guide thereof which is radial relative to the coil (1).
 5. Aholding device according to claim 4, characterized in that the clampingand guiding devices (36) are supportable with a positive fit on toothingsystems of guide rods (43) of the clamping device (36), viaspring-loaded latches (40).
 6. A holding device according to any ofclaim 1, characterized in that the clamping bar (44) is movable againstthe clamping direction by means of actuators engaging the clampingdevices (36) for the purpose of lifting the clamping bar (34) from thecoil (1).
 7. A holding device according to claim 6, characterized inthat the actuators (46) are supportable on support lugs (41, 42) of theclamping device (36).
 8. A holding device according to any of claim 5,characterized in that the guide rods (43) of the clamping device (36)are received in bearing pieces (45) which are rotatably mounted onto thecarrying shaft (44).
 9. A holding device according to any of claim 6,characterized in that final positions of the support lugs (41) and (42)end up lying symmetrically to the plane of the sheet end (12) with theactuators (46) being spread apart so that opening and closing of theholding device can be accomplished by an actuator (46) independently ofthe desired unwinding variant.
 10. A holding device according to any ofclaim 1, characterized in that the distance between the carrying shaft(44) and the clamping bar (34) is reducible during an unwindingoperation according to the decrease in the diameter of the coil.
 11. Aholding device according to claim 10, characterized in that, with adecreasing unwinding radius of the coil (1), the spring-loaded latches(40) will lock into place on toothing systems of the guide rods (43)according to said decrease.
 12. A holding device according to claim 3,characterized in that, during the assembly of the clamping bar (34), thebearing pieces (45) are fixable on the carrying shaft (44) in a desiredperipheral position using fixing devices (48).
 13. A holding deviceaccording to claim 5, characterized in that the clamping device (36)comprises a compression spring (39) acting between the guide rod (43)and the clamping bar (34).
 14. A holding device according to claim 13,characterized in that the compression spring (39) can be prestressed byan eccentric lever (47) supportable on the support lugs (41, 42), one ofthem being associated to the guide rod (43) and the other one beingassociated to the clamping bar (34).